An interval linear traffic planning model is developed for supporting vehicle emissions limited under uncertainty. The interval linear traffic planning model can address uncertainties of traffic system and vehicle emi...An interval linear traffic planning model is developed for supporting vehicle emissions limited under uncertainty. The interval linear traffic planning model can address uncertainties of traffic system and vehicle emissions related to system costs and limitation of emission. The interval linear traffic planning model is applicable to complex traffic system. One virtual city as our study object was taken by using the interval linear traffic planning model. In this study, one virtual case and a scenario are provided for three planning periods. The results indicate that the interval linear traffic planning model can effectively reduce the vehicles emission and provide strategies for authorities to deal with problems of transportation system.展开更多
Reviewing the existing environmental policies in Western China,we find that:in time sequence,the characteristics of China's western environmental policies shift from"development drive governance"to the f...Reviewing the existing environmental policies in Western China,we find that:in time sequence,the characteristics of China's western environmental policies shift from"development drive governance"to the full implementation of environmental protection and construction;and in spatial sequence,the ecological,social,and economic development of Western China reach to coordination through the nature reserve setting,ecological migrants,fiscal transfer payment and differentiated ecological environmental policies.Due to the implementation of the policies and projects,environmental degradation trends in the western ecological environment were alleviated significantly,the living conditions of farmers and herdsmen were improved,and many successful experiences were explored.However,future ecological environmental construction in Western China requires further improvement in integrated planning,eco-compensation mechanism,and policy assessment.This paper concludes with specific recommendations such as drawing up ecological environment construction planning,strengthening environmental law enforcement and incentive mechanisms,improving policy assessment and scientific support,enhancing environmental protection capacity,improving eco-compensation mechanism,and refining the environmental policies for key areas.展开更多
Watersheds provide a variety of ecological services including soil and water conservation, carbon sequestration and biodiversity protection. However, activities in a fast-growing economy significantly impact the suppl...Watersheds provide a variety of ecological services including soil and water conservation, carbon sequestration and biodiversity protection. However, activities in a fast-growing economy significantly impact the supply and demand of these watershed services. To mitigate these impacts, the concept of payment for environmental and ecosystem services from water-sheds has emerged in global academic and policy circles. The governments and academic communities in China have increas-ingly described payments for ecological services from watersheds with the concept of watershed eco-compensation as it is urgent to protect watershed ecosystems. Watershed eco-compensation has proved to be one of the most economically effective means of solving environmental problems of watersheds to be adopted by the Chinese government. This paper presents an objective analysis of the Chinese market for watershed ecosystem services, including supply and demand for the services. It also summarizes Chinese policies on watershed eco-compensation, including relevant laws and regulations and fiscal policies. In addition, it presents a re-view of Chinese practices in watershed eco-compensation, in-cluding the analysis of an ecological construction project in West-ern China, inter-provincial watershed eco-compensation practices and plans, and payment for ecological services at the provincial and small watershed levels. Finally, it summarizes the key com-ponents of the process of payment in Chinese watershed eco-compensation. This discussion forms the basis of concluding suggestions for ecosystem services compensation and ecological protection in the large scale river basin.展开更多
At present about 60% of ecosystem has been damaged and degraded severely, resulting in enormous ecological loss globally. The essential cause is the irrational utilization of ecosystem by humankind, so it is tire key ...At present about 60% of ecosystem has been damaged and degraded severely, resulting in enormous ecological loss globally. The essential cause is the irrational utilization of ecosystem by humankind, so it is tire key to changing improper environmental performance of humankind so as to prevent ecosystem from being damaged The quantitative valuation on the loss of ecological damage is an effective tool to guide human eco-environmental performance. In this paper, the concepts related to the valuation on ecological damage cost are introduced," uncertainties that might arise in the valuation on the loss of ecological damage such as area coverage of valuation, ecological damage quantity, borders of ecological damage cost and data support are analyzed and the valuation approaches for the loss of ecological damage are also discussed As a case study, the economic losses of ecological damage of forest in 2005 in China are valuated.展开更多
Water quality in China is becoming a severe challenge for agriculture and food safety, and it might also impact health of population via agriculture and food. Thus, it is causing widespread concern. Based on extensive...Water quality in China is becoming a severe challenge for agriculture and food safety, and it might also impact health of population via agriculture and food. Thus, it is causing widespread concern. Based on extensive literatures review and data mining, current situation of water pollution in China and its effects on food safety were analyzed. The 2nd National Water Resource Survey in China show that the surface water all over the country was under slight pollution and about 60% of groundwater is polluted. Drinking water quality is basically guaranteed in urban area but it is worrisome in rural areas. In addition, China is the largest consumer of fertilizer and pesticide in the world and the amounts of application still show increasing trends. Fertilizers and pesticides are the most important sources of pollution, which affect human health as persistent organic pollutants and environmental endocrine disruptors. Eutrophication of surface water and nitrate pollution of groundwater are serious threats to drinking water safety. Sewage irrigation is becoming a pollution source to China's water and land because of lacking of effective regulations. Although, with the advance in technology and management level, control of nitrogen and phosphorus emissions and reducing water pollution is still a major challenge for China.展开更多
The methane(CH4) emissions from municipal solid waste(MSW) landfills in China in 2007 were estimated based on database of the three-dimensional emission factors matrix and point sources, by an IPCC recommended FOD(fir...The methane(CH4) emissions from municipal solid waste(MSW) landfills in China in 2007 were estimated based on database of the three-dimensional emission factors matrix and point sources, by an IPCC recommended FOD(firstorder decay) model. The location, capacity and age of landfills constitute the three dimensions of the emission factors matrix, which were obtained by laboratory analysis and in situ investigation. Key parameters such as waste composition,degradable organic carbon ratio, CH4 correction factor, oxidation factor and recovery rate, were carefully analyzed in terms of these three dimensions. The point sources database consists of 2,107 MSW landfills in cities and towns of China in 2007. The results show that the CH4 emissions from MSW landfills were 1.186 Mt in 2007. Compared with the CH4 emissions of 2.20 Mt in 2005, the significant discrepancy mainly comes from statistical data of landfills, e.g., number of landfills and amount of waste disposed in landfills. CH4 emissions were lower than 700 t for most of the landfills, whereas there were 279 landfills with emissions larger than 1,000 t, and only 10 landfills with emissions larger than 10,000 t.Jiangsu province ranks the largest emitter with 98,700 t while Tibet is the smallest emitter with 2,100 t. In general,the emissions from eastern provinces, such as Jiangsu, Guangdong and Zhejiang, were larger than those from western provinces, such as Ningxia, Tibet and Qinghai.展开更多
Based on the China high resolution emission gridded data (I km spatial resolution), this article is aimed to create a Chinese city carbon dioxide (CO2) emission data set using consolidated data sources as well as ...Based on the China high resolution emission gridded data (I km spatial resolution), this article is aimed to create a Chinese city carbon dioxide (CO2) emission data set using consolidated data sources as well as normalized and standardized data processing methods. Standard methods were used to calculate city CO2 emissions, including scope I and scope 2. Cities with higher CO2 emissions are mostly in north, northeast, and eastern coastal areas. Cities with lower CO2 emissions are in the western region. Cites with higher CO2 emissions are clustered in the Jing-Jin-Ji Region (such as Beijing, Tianjin, and Tangshan), and the Yangtze River Delta region (such as Shanghai and Suzhou). The city per capita CO2 emission is larger in the north than the south. There are obvious aggregations of cities with high per capita CO2 emission in the north. Four cities among the top 10 per capita emissions (Erdos, Wuhai, Shizuishan, and Yinchuan) cluster in the main coal production areas of northern China. This indicates the significant impact of coal resources endowment on city industry and CO2 emissions. The majority (77%) of cities have annual CO2 emissions below 50 million tons. The mean annual emission, among all cities, is 37 million tons. Emissions from service-based cities, which include the smallest number of cities, are the highest. Industrial cities are the largest category and the emission distribution from these cities is close to the normal distribution. Emissions and degree of dispersion, in the other cities (excluding industrial cities and service-based cities), are in the lowest level. Per capita CO2 emissions in these cities are generally below 20 t/person (89%) with a mean value of 11 t/person. The distribution interval of per capita CO2 emission within industrial cities is the largest among the three city categories. This indicates greater differences among per capita CO2 emissions of industrial cities. The distribution interval of per capita CO2 emission of other cities is the lowest, indicating smaller differences of per capita CO2 emissions among this city category. Three policy suggestions are proposed: first, city CO2 emission inventory data in China should be increased, especially for prefecture level cities. Second, city responsibility for emission reduction, and partition- ing the national goal should be established, using a bottom-up approach based on specific CO2 emission levels and potential for emission reductions in each city. Third, comparative and bench- marking research on city CO2 emissions should be conducted, and a Top Runner system of city CO2 emission reduction should be established.展开更多
The ecological protection of the watersheds in China is being confronted with a lot of problems such as soil and water erosion, water pollution at present. Therefore watershed eco-compensation is becoming a question o...The ecological protection of the watersheds in China is being confronted with a lot of problems such as soil and water erosion, water pollution at present. Therefore watershed eco-compensation is becoming a question of common interest. Based on the analyses of the major problems and their origins in the watershed protection in China, the paper discusses the concerned policies including relative rules and laws, financial policies and water right transaction policies. Simultaneously the paper reviews the practices carried out in China, including the ecological construction project in the western China, the trans-provincial eco-compensation practice and the small watershed eco-compensation practice. According to the present situation of eco-compensation practices and the future policy requirement, this paper finally puts forward four key problems to be solved in the watershed eco-compensation of China in the future.展开更多
Two plant populations of Phragmites australis and Typha orientalis grown in gravel and sediment substrate were studied to assess their capabilities for purifying polluted water in Taihu Lake, China. The substrate disp...Two plant populations of Phragmites australis and Typha orientalis grown in gravel and sediment substrate were studied to assess their capabilities for purifying polluted water in Taihu Lake, China. The substrate displayed most significant effects on the suspended matter (P 〈 0.01), with the reduction of 76%-87% and 52%--63% for P. australis, and 83%-86% and 45%-62% for T. orientalis in gravel substrate and sediment substrate, respectively. Both species and substrates significantly decreased the N and P concentrations of water body (P 〈 0.01). P. australis showed higher total N and P concentrations in tissues than T. orientalis and had a greater potential to remove nutrients from the lake. Phosphate was easily to concentrate in the belowground tissues, while nitrate concentration was higher in leaf and stalk. Therefore, harvesting the aboveground tissues could take most of nitrate out of the sediment. The saturate photosynthetic rate (Asat) of P. australis was higher than that of T. orientalis when grown in sediment substrate. But instance water-use- efficiency (WUEi) (A/E) and intrinsic water use efficiency (A/gs) showed the maximum values of two species grown in river water. With significant difference in gs, however, intercellular CO2 concentration (Ci) had no obvious difference in two species which indicated that high Asat value of P. australis might result from the increased carboxylation capacity of the mesophyll, because of the central role of N in photosynthetic enzymes. Our findings suggest that the plants could absorb most of nitrogen in polluted water, while gravel displayed a high capacity for absorbing the suspended matters and phosphate salts. Therefore, biological and physiological pathways for pollutant removal should be integrated.展开更多
This study aimed to accurately study the intra-annual spatiotemporal variation in the surface urban heat island intensities(SUHIIs) in 1449 cities in China.First, China was divided into five environmental regions.Then...This study aimed to accurately study the intra-annual spatiotemporal variation in the surface urban heat island intensities(SUHIIs) in 1449 cities in China.First, China was divided into five environmental regions.Then, the SUHIIs were accurately calculated based on the modified definitions of the city extents and their corresponding nearby rural areas.Finally, we explored the spatiotemporal variation of the mean, maximum, and minimum values, and ranges of SUHIIs from several aspects.The results showed that larger annual mean daytime SUHIIs occurred in hot-humid South China and cold-humid northeastern China, and the smallest occurred in arid and semiarid west China.The seasonal order of the SUHIIs was summer > spring > autumn > winter in all the temperate regions except west China.The SUHIIs were obviously larger during the rainy season than the dry season in the tropical region.Nevertheless, significant differences were not observed between the two seasons within the rainy or dry periods.During the daytime, the maximum SUHIIs mostly occurred in summer in each region, while the minimum occurred in winter.A few cold island phenomena existed during the nighttime.The maximum SUHIIs were generally significantly positively correlated with the minimum SUHIIs during the daytime, nighttime and all-day in all environmental regions throughout the year and the four seasons.Moreover, significant correlation scarcely existed between the daytime and nighttime ranges of the SUHIIs.In addition, the daytime SUHIIs were also insignificantly correlated with the nighttime SUHIIs in half of the cases.展开更多
As part of a comprehensive environmental management system, many countries establish emission control targets for mass emissions of a pollutant. Such targets are often the key objective of an environmental policy, suc...As part of a comprehensive environmental management system, many countries establish emission control targets for mass emissions of a pollutant. Such targets are often the key objective of an environmental policy, such as an emission trading program. In China, however, it is more than just an objective of one particular policy; it has become a concept that has influenced many national environmental policies and activities. The objective of this article is to review the implementation of the total emission control policy in the past 10 years and explore emerging issues in its implementation. The article has three sections: a summary of the implementation experience, issues with the design and implementation of the policy, and policy recommendations.展开更多
The impacts of the meteorological condition and emissions reduction on the aerosol concentration over the Beijing-Tianjin-Hebei(BTH) region during the COVID-19 lockdown were analyzed by conducting three numerical expe...The impacts of the meteorological condition and emissions reduction on the aerosol concentration over the Beijing-Tianjin-Hebei(BTH) region during the COVID-19 lockdown were analyzed by conducting three numerical experiments,including one with the meteorological field in 2019 and MEIC-2019(2019 monthly Multi-resolution Emissions Inventory for China),one with the meteorological field in 2020 and MEIC-2019,and one with the meteorological field in 2020 and MEIC-2020,via a WRF-Chem model.The numerical experiments were performed from 3 to 16 February in 2019 and in 2020,during which a severe fog-haze event(3-16 February 2020) occurred in the BTH region,with a simulated maximum daily PM2.5 of 245μg m-3 in Tangshan and 175μg m-3 in Beijing.The results indicate that the daily PM2.5 decreased by 5-150μg m-3 due to the emissions reduction and increased by 10-175 μg m-3 due to the meteorological condition in Beijing,Shijiazhuang,Cangzhou,Handan,Hengshui,Chengde,Zhangjiakou,and Tangshan from 7 to 14 February.For the horizontal distribution,PM2.5 and different aerosol species concentrations from 7 to 14 February 2020 increased compared with those during the same period in 2019,indicating that the accumulation of pollutants caused by the unfavorable meteorological condition offset the decreases caused by the emissions reduction,leading to the high aerosol concentration during the COVID-19 lockdown.展开更多
Nowadays the rising of opportunity cost of farm labor comes to the forefront of attention in China. In order to understand its impact on agricultural land-use structure, a theoretical framework of household economics ...Nowadays the rising of opportunity cost of farm labor comes to the forefront of attention in China. In order to understand its impact on agricultural land-use structure, a theoretical framework of household economics is formulated drawn on Low's model. Under the theoretical framework, the impact of the rising opportunity cost of on-farm on cropping structure is deduced in theory. And then, using statistic and survey data, taking mountain area of southern Ningxia as an example, the theoretical assumes are verified. The results show that the rise of opportunity cost of farm labor leads to less diversified cropping structure.展开更多
1.Present characteristics of Beijing's energy consumption 1.1 The slowing of the growth in total energy consumption In 2008,Beijing's total energy consumption reached 63.437 million tons of standard coal,an in...1.Present characteristics of Beijing's energy consumption 1.1 The slowing of the growth in total energy consumption In 2008,Beijing's total energy consumption reached 63.437 million tons of standard coal,an increase of 586.6 thousand tons compared with the previous year.The increasing range was 1%,dropping 5.45%compared with the展开更多
In this paper,using concentration data of PM2. 5in 2013 in China and referring to a lot of literature,we preliminary studied the pollution of fine particulate matter and summarized PM2. 5source apportionment in the ke...In this paper,using concentration data of PM2. 5in 2013 in China and referring to a lot of literature,we preliminary studied the pollution of fine particulate matter and summarized PM2. 5source apportionment in the key cities in China. Our results showed that PM2. 5showed significant spatial and temporal distribution; high surface concentrations of PM2. 5concentrated mainly in the North China Plain,the Sichuan Basin,Yangtze River Delta and other regions; the average annual concentration of PM2. 5was about 80μg / m3 in North China Plain; Seasonal changes in the concentration of PM2. 5was winter > spring > autumn > summer; fired sources,industrial sources,vehicle exhaust were the major sources of PM2. 5; motor vehicle exhaust mostly contributed 10%- 30% to PM2. 5. This review provides a fundamental understanding of PM2. 5source apportionment and serves as an important reference for future source apportionment studies to be widely conducted in China.展开更多
Many environmental variables are frequently used to predict values of soil in locations where they are not measured. Digital soil mapping (DSM) has a long-standing convention to describe soils as a function of climate...Many environmental variables are frequently used to predict values of soil in locations where they are not measured. Digital soil mapping (DSM) has a long-standing convention to describe soils as a function of climate, organisms, topography, parent material, time and space. It is obvious that terrain, climate, parent material and organisms are used frequently in the prediction of soil properties while time and space factors are rarely used. Time is the indirect factor for the formation and development of soil. Moreover, it is very useful to explicit and implicit estimates of soil age for DSM. However, it is often difficult to obtain time factor. In the absence of explicit soil age data, geomorphologic data are commonly related to soil relative age. Consequently, this study adopts the geomorphologic types (genesis type of geomorphology) as surrogate to the time factor and analyzes its effect on DSM. To examine this idea, we selected the Ili region of northwestern China as the study area. This paper uses geomorphologic data from a new digital geomorphology map as the implicit soil age in predictive soil mapping. For this study, Soil-landscape inference model (SoLIM) was used to predict soil properties based on the individual representation of each sample. This model applies the terrain (topography), climate, parent material (geology) and time (geomorphologic type) to predict soil values in the study area where they are not measured. And the independent sample validation method was used to estimate the precision of results. The validation result shows that the use of geomorphologic data as surrogate to the time factor in the individual representation leads to a considerable and significant increase in the accuracy of results. In other words, implicit estimates of soil age by genesis type of geomorphology are very useful for DSM. This increase was due to the high purity of the geomorphologic data. This means that the geomorphologic variable, if used, can improve the quality of DSM. Predicted value through the proposed approach comes closer to the real value.展开更多
In this paper,narrow-pulse power discharge is used to study the synergistic control of mercury and dioxins,in which 1,2,4-trichlorobenzene(TCB)was used as a dioxin analog,by using a selfdesigned experimental system.Th...In this paper,narrow-pulse power discharge is used to study the synergistic control of mercury and dioxins,in which 1,2,4-trichlorobenzene(TCB)was used as a dioxin analog,by using a selfdesigned experimental system.The competitive effects of NO,SO2 and HC1 on the TCB removal by non-thermal plasma are discussed.The influence of acid gas on TCB degradation is reflected in the competitive effect.NO has the greatest influence on TCB degradation efficiency.The oxidation efficiency of Hg°decreased by about 10%in all three acidic gas atmospheres,and the effect of each gas component on Hg()oxidation is complex.In the flue gas atmosphere of'acid gas+Hg°+TCB',the mechanism of the synergistic control of Hg°and TCB by the nonthermal plasma is different,which has competition and promotion relationship between each other.The contribution of various flue gas components to the results was complicated,but the overall experimental results show that the synergistic control effect of the system can continue to improve.According to the generated product backstepping,-OH plays an important role in the synergistic control of the degradation of Hg°and TCB.Through this study,we hope to provide basic research data for the collaborative control of flue gas in the incineration industry.展开更多
A cryogenic scanning electron microscopy(cryo-SEM) technique was used to explore the shear-thickening behavior of Fe-ZSM5 zeolite pastes and to discover its underlying mechanism. Bare Fe-ZSM5 zeolite samples were fo...A cryogenic scanning electron microscopy(cryo-SEM) technique was used to explore the shear-thickening behavior of Fe-ZSM5 zeolite pastes and to discover its underlying mechanism. Bare Fe-ZSM5 zeolite samples were found to contain agglomerations, which may break the flow of the pastes and cause shear-thickening behaviors. However, the shear-thickening behaviors can be eliminated by the addition of halloysite and various boehmites because of improved particle packing. Furthermore, compared with pure Fe-ZSM5 zeolite samples and its composite samples with halloysite, the samples with boehmite(Pural SB or Disperal) additions exhibited network structures in their cryo-SEM images; these structures could facilitate the storage and release of flow water, smooth paste flow, and avoid shear-thickening. By contrast, another boehmite(Versal 250) formed agglomerations rather than network structures after being added to the Fe-ZSM5 zeolite paste and resulted in shear-thickening behavior. Consequently, the results suggest that these network structures play key roles in eliminating the shear-thickening behavior.展开更多
Effects of conservation methods of water samples on determination of total phosphorus were analyzed from aspects of methods of adding conserving agent, SS concentration, natural sedimentation time, conservation temper...Effects of conservation methods of water samples on determination of total phosphorus were analyzed from aspects of methods of adding conserving agent, SS concentration, natural sedimentation time, conservation temperature and time. The results showed that SS concentration in water and natural sedimentation time had the greatest impact on the determination of total phosphorus, while the influence of methods of adding conserving agent, conservation temperature and time was relatively smaller. TP concentration in water samples conserved irregularly was higher than the standard value due to the existence of SS and microorganisms in water, and the deviation became larger with the increase of SS concentration in water. In addition, quality control measures and matters needing attention during the conservation process of water samples were put forward to improve the accuracy of TP concentration.展开更多
[Objective] This study aimed to examine indicative roles of texture representing soil organic carbon presence and variability subsequent to cultivation under cold temperate climates with seasonal freeze-thaw events. [...[Objective] This study aimed to examine indicative roles of texture representing soil organic carbon presence and variability subsequent to cultivation under cold temperate climates with seasonal freeze-thaw events. [Method] Three chronosequences were selected for paired comparisons. Soil samples were collected at six depths with a 10 cm increment. Analysis of variance with general linear model and regression was performed for statistical analysis. [Result] In seasonally frozen soils where fragmentation of macroaggregates was stimulated, soil organic carbon level was positively associated with clay + silt proportion due to a wider textural range, better than sole clay content. Exponential function better fitted the experimental data to present progressively increased effectiveness of clay + silt content in maintaining carbon. Clay content explained 12%-41% and 14%-43% of variation via linear and exponential functions, respectively. Accordingly, clay + silt content explained 47%-65% and 46%-70%. [Conclusion] Texture reflected soil organic carbon occurrence as consequences of reclamation. For seasonally frozen soils with wider textural ranges, it is robust to adapt clay + silt content as dependent variable and exponential function. The generated algorithms provided an available pathway to estimate soil organic carbon losses following cultivation and to evaluate soil fertility.展开更多
文摘An interval linear traffic planning model is developed for supporting vehicle emissions limited under uncertainty. The interval linear traffic planning model can address uncertainties of traffic system and vehicle emissions related to system costs and limitation of emission. The interval linear traffic planning model is applicable to complex traffic system. One virtual city as our study object was taken by using the interval linear traffic planning model. In this study, one virtual case and a scenario are provided for three planning periods. The results indicate that the interval linear traffic planning model can effectively reduce the vehicles emission and provide strategies for authorities to deal with problems of transportation system.
基金financially supported by the"Strategy and Policies on Environment and Development in Western China"project
文摘Reviewing the existing environmental policies in Western China,we find that:in time sequence,the characteristics of China's western environmental policies shift from"development drive governance"to the full implementation of environmental protection and construction;and in spatial sequence,the ecological,social,and economic development of Western China reach to coordination through the nature reserve setting,ecological migrants,fiscal transfer payment and differentiated ecological environmental policies.Due to the implementation of the policies and projects,environmental degradation trends in the western ecological environment were alleviated significantly,the living conditions of farmers and herdsmen were improved,and many successful experiences were explored.However,future ecological environmental construction in Western China requires further improvement in integrated planning,eco-compensation mechanism,and policy assessment.This paper concludes with specific recommendations such as drawing up ecological environment construction planning,strengthening environmental law enforcement and incentive mechanisms,improving policy assessment and scientific support,enhancing environmental protection capacity,improving eco-compensation mechanism,and refining the environmental policies for key areas.
基金This paper is supported by the National Socia Science Foundation of China (Grant No.06&ZD038) Young Tech nological Innovation Foundation of CAEP (Grant No 2007001 ).
文摘Watersheds provide a variety of ecological services including soil and water conservation, carbon sequestration and biodiversity protection. However, activities in a fast-growing economy significantly impact the supply and demand of these watershed services. To mitigate these impacts, the concept of payment for environmental and ecosystem services from water-sheds has emerged in global academic and policy circles. The governments and academic communities in China have increas-ingly described payments for ecological services from watersheds with the concept of watershed eco-compensation as it is urgent to protect watershed ecosystems. Watershed eco-compensation has proved to be one of the most economically effective means of solving environmental problems of watersheds to be adopted by the Chinese government. This paper presents an objective analysis of the Chinese market for watershed ecosystem services, including supply and demand for the services. It also summarizes Chinese policies on watershed eco-compensation, including relevant laws and regulations and fiscal policies. In addition, it presents a re-view of Chinese practices in watershed eco-compensation, in-cluding the analysis of an ecological construction project in West-ern China, inter-provincial watershed eco-compensation practices and plans, and payment for ecological services at the provincial and small watershed levels. Finally, it summarizes the key com-ponents of the process of payment in Chinese watershed eco-compensation. This discussion forms the basis of concluding suggestions for ecosystem services compensation and ecological protection in the large scale river basin.
文摘At present about 60% of ecosystem has been damaged and degraded severely, resulting in enormous ecological loss globally. The essential cause is the irrational utilization of ecosystem by humankind, so it is tire key to changing improper environmental performance of humankind so as to prevent ecosystem from being damaged The quantitative valuation on the loss of ecological damage is an effective tool to guide human eco-environmental performance. In this paper, the concepts related to the valuation on ecological damage cost are introduced," uncertainties that might arise in the valuation on the loss of ecological damage such as area coverage of valuation, ecological damage quantity, borders of ecological damage cost and data support are analyzed and the valuation approaches for the loss of ecological damage are also discussed As a case study, the economic losses of ecological damage of forest in 2005 in China are valuated.
基金the Shenzhen Science and Technology Projects of China (JCYJ20140417144423187 and JCYJ20130331145022339)Shenzhen Engineering Laboratory for Water Desalinization with Renewable Energy, China
文摘Water quality in China is becoming a severe challenge for agriculture and food safety, and it might also impact health of population via agriculture and food. Thus, it is causing widespread concern. Based on extensive literatures review and data mining, current situation of water pollution in China and its effects on food safety were analyzed. The 2nd National Water Resource Survey in China show that the surface water all over the country was under slight pollution and about 60% of groundwater is polluted. Drinking water quality is basically guaranteed in urban area but it is worrisome in rural areas. In addition, China is the largest consumer of fertilizer and pesticide in the world and the amounts of application still show increasing trends. Fertilizers and pesticides are the most important sources of pollution, which affect human health as persistent organic pollutants and environmental endocrine disruptors. Eutrophication of surface water and nitrate pollution of groundwater are serious threats to drinking water safety. Sewage irrigation is becoming a pollution source to China's water and land because of lacking of effective regulations. Although, with the advance in technology and management level, control of nitrogen and phosphorus emissions and reducing water pollution is still a major challenge for China.
基金funded by the Project Study on Key Issues of China City Carbon Emission Inventory (No. 41101500)supported by National Natural Science Foundation of China
文摘The methane(CH4) emissions from municipal solid waste(MSW) landfills in China in 2007 were estimated based on database of the three-dimensional emission factors matrix and point sources, by an IPCC recommended FOD(firstorder decay) model. The location, capacity and age of landfills constitute the three dimensions of the emission factors matrix, which were obtained by laboratory analysis and in situ investigation. Key parameters such as waste composition,degradable organic carbon ratio, CH4 correction factor, oxidation factor and recovery rate, were carefully analyzed in terms of these three dimensions. The point sources database consists of 2,107 MSW landfills in cities and towns of China in 2007. The results show that the CH4 emissions from MSW landfills were 1.186 Mt in 2007. Compared with the CH4 emissions of 2.20 Mt in 2005, the significant discrepancy mainly comes from statistical data of landfills, e.g., number of landfills and amount of waste disposed in landfills. CH4 emissions were lower than 700 t for most of the landfills, whereas there were 279 landfills with emissions larger than 1,000 t, and only 10 landfills with emissions larger than 10,000 t.Jiangsu province ranks the largest emitter with 98,700 t while Tibet is the smallest emitter with 2,100 t. In general,the emissions from eastern provinces, such as Jiangsu, Guangdong and Zhejiang, were larger than those from western provinces, such as Ningxia, Tibet and Qinghai.
基金funded by the project entitled"An Emission-Transport-Exposure Model Based Study on the Evaluation of the Environmental Impact of Carbon Market"[grant number:71673107]supported by the National Natural Science Foundation of China
文摘Based on the China high resolution emission gridded data (I km spatial resolution), this article is aimed to create a Chinese city carbon dioxide (CO2) emission data set using consolidated data sources as well as normalized and standardized data processing methods. Standard methods were used to calculate city CO2 emissions, including scope I and scope 2. Cities with higher CO2 emissions are mostly in north, northeast, and eastern coastal areas. Cities with lower CO2 emissions are in the western region. Cites with higher CO2 emissions are clustered in the Jing-Jin-Ji Region (such as Beijing, Tianjin, and Tangshan), and the Yangtze River Delta region (such as Shanghai and Suzhou). The city per capita CO2 emission is larger in the north than the south. There are obvious aggregations of cities with high per capita CO2 emission in the north. Four cities among the top 10 per capita emissions (Erdos, Wuhai, Shizuishan, and Yinchuan) cluster in the main coal production areas of northern China. This indicates the significant impact of coal resources endowment on city industry and CO2 emissions. The majority (77%) of cities have annual CO2 emissions below 50 million tons. The mean annual emission, among all cities, is 37 million tons. Emissions from service-based cities, which include the smallest number of cities, are the highest. Industrial cities are the largest category and the emission distribution from these cities is close to the normal distribution. Emissions and degree of dispersion, in the other cities (excluding industrial cities and service-based cities), are in the lowest level. Per capita CO2 emissions in these cities are generally below 20 t/person (89%) with a mean value of 11 t/person. The distribution interval of per capita CO2 emission within industrial cities is the largest among the three city categories. This indicates greater differences among per capita CO2 emissions of industrial cities. The distribution interval of per capita CO2 emission of other cities is the lowest, indicating smaller differences of per capita CO2 emissions among this city category. Three policy suggestions are proposed: first, city CO2 emission inventory data in China should be increased, especially for prefecture level cities. Second, city responsibility for emission reduction, and partition- ing the national goal should be established, using a bottom-up approach based on specific CO2 emission levels and potential for emission reductions in each city. Third, comparative and bench- marking research on city CO2 emissions should be conducted, and a Top Runner system of city CO2 emission reduction should be established.
文摘The ecological protection of the watersheds in China is being confronted with a lot of problems such as soil and water erosion, water pollution at present. Therefore watershed eco-compensation is becoming a question of common interest. Based on the analyses of the major problems and their origins in the watershed protection in China, the paper discusses the concerned policies including relative rules and laws, financial policies and water right transaction policies. Simultaneously the paper reviews the practices carried out in China, including the ecological construction project in the western China, the trans-provincial eco-compensation practice and the small watershed eco-compensation practice. According to the present situation of eco-compensation practices and the future policy requirement, this paper finally puts forward four key problems to be solved in the watershed eco-compensation of China in the future.
基金supported by the Control and Treatment of Water Pollution Implementation Scheme of the National Important Science and Technology Project(No. 2008ZX07526-002)the Hi-Tech Research and Development Program (863) of China (No. 2002AA601012-06)the National Basic Research Program (973) of China (No. 2002CB412409)
文摘Two plant populations of Phragmites australis and Typha orientalis grown in gravel and sediment substrate were studied to assess their capabilities for purifying polluted water in Taihu Lake, China. The substrate displayed most significant effects on the suspended matter (P 〈 0.01), with the reduction of 76%-87% and 52%--63% for P. australis, and 83%-86% and 45%-62% for T. orientalis in gravel substrate and sediment substrate, respectively. Both species and substrates significantly decreased the N and P concentrations of water body (P 〈 0.01). P. australis showed higher total N and P concentrations in tissues than T. orientalis and had a greater potential to remove nutrients from the lake. Phosphate was easily to concentrate in the belowground tissues, while nitrate concentration was higher in leaf and stalk. Therefore, harvesting the aboveground tissues could take most of nitrate out of the sediment. The saturate photosynthetic rate (Asat) of P. australis was higher than that of T. orientalis when grown in sediment substrate. But instance water-use- efficiency (WUEi) (A/E) and intrinsic water use efficiency (A/gs) showed the maximum values of two species grown in river water. With significant difference in gs, however, intercellular CO2 concentration (Ci) had no obvious difference in two species which indicated that high Asat value of P. australis might result from the increased carboxylation capacity of the mesophyll, because of the central role of N in photosynthetic enzymes. Our findings suggest that the plants could absorb most of nitrogen in polluted water, while gravel displayed a high capacity for absorbing the suspended matters and phosphate salts. Therefore, biological and physiological pathways for pollutant removal should be integrated.
基金Under the auspices of National Natural Science Foundation of China(No.41901238,41701501)Social Science Fund of China(General Projects)(No.17BJL065)+1 种基金Key Scientific and Technological Project of Henan Province(No.192102310003)Educational Commission of Henan Province(No.2019-ZZJH-094)
文摘This study aimed to accurately study the intra-annual spatiotemporal variation in the surface urban heat island intensities(SUHIIs) in 1449 cities in China.First, China was divided into five environmental regions.Then, the SUHIIs were accurately calculated based on the modified definitions of the city extents and their corresponding nearby rural areas.Finally, we explored the spatiotemporal variation of the mean, maximum, and minimum values, and ranges of SUHIIs from several aspects.The results showed that larger annual mean daytime SUHIIs occurred in hot-humid South China and cold-humid northeastern China, and the smallest occurred in arid and semiarid west China.The seasonal order of the SUHIIs was summer > spring > autumn > winter in all the temperate regions except west China.The SUHIIs were obviously larger during the rainy season than the dry season in the tropical region.Nevertheless, significant differences were not observed between the two seasons within the rainy or dry periods.During the daytime, the maximum SUHIIs mostly occurred in summer in each region, while the minimum occurred in winter.A few cold island phenomena existed during the nighttime.The maximum SUHIIs were generally significantly positively correlated with the minimum SUHIIs during the daytime, nighttime and all-day in all environmental regions throughout the year and the four seasons.Moreover, significant correlation scarcely existed between the daytime and nighttime ranges of the SUHIIs.In addition, the daytime SUHIIs were also insignificantly correlated with the nighttime SUHIIs in half of the cases.
文摘As part of a comprehensive environmental management system, many countries establish emission control targets for mass emissions of a pollutant. Such targets are often the key objective of an environmental policy, such as an emission trading program. In China, however, it is more than just an objective of one particular policy; it has become a concept that has influenced many national environmental policies and activities. The objective of this article is to review the implementation of the total emission control policy in the past 10 years and explore emerging issues in its implementation. The article has three sections: a summary of the implementation experience, issues with the design and implementation of the policy, and policy recommendations.
基金This study was supported by the National Key R&D Program of China[grant number 2017YFB0503901)the National Natural Science Foundation of China[grant numbers 41830109 and 41830966]the Major Scientific and Technological Innovation Projects of Shandong Province[grant number 2018YFJH0901].
文摘The impacts of the meteorological condition and emissions reduction on the aerosol concentration over the Beijing-Tianjin-Hebei(BTH) region during the COVID-19 lockdown were analyzed by conducting three numerical experiments,including one with the meteorological field in 2019 and MEIC-2019(2019 monthly Multi-resolution Emissions Inventory for China),one with the meteorological field in 2020 and MEIC-2019,and one with the meteorological field in 2020 and MEIC-2020,via a WRF-Chem model.The numerical experiments were performed from 3 to 16 February in 2019 and in 2020,during which a severe fog-haze event(3-16 February 2020) occurred in the BTH region,with a simulated maximum daily PM2.5 of 245μg m-3 in Tangshan and 175μg m-3 in Beijing.The results indicate that the daily PM2.5 decreased by 5-150μg m-3 due to the emissions reduction and increased by 10-175 μg m-3 due to the meteorological condition in Beijing,Shijiazhuang,Cangzhou,Handan,Hengshui,Chengde,Zhangjiakou,and Tangshan from 7 to 14 February.For the horizontal distribution,PM2.5 and different aerosol species concentrations from 7 to 14 February 2020 increased compared with those during the same period in 2019,indicating that the accumulation of pollutants caused by the unfavorable meteorological condition offset the decreases caused by the emissions reduction,leading to the high aerosol concentration during the COVID-19 lockdown.
基金support of research grants from the National Key Technology R&D Program(Grant No.2006BAB15B02)the National Natural Science Fund of China(Grant No.40971062 and 404801051)
文摘Nowadays the rising of opportunity cost of farm labor comes to the forefront of attention in China. In order to understand its impact on agricultural land-use structure, a theoretical framework of household economics is formulated drawn on Low's model. Under the theoretical framework, the impact of the rising opportunity cost of on-farm on cropping structure is deduced in theory. And then, using statistic and survey data, taking mountain area of southern Ningxia as an example, the theoretical assumes are verified. The results show that the rise of opportunity cost of farm labor leads to less diversified cropping structure.
文摘1.Present characteristics of Beijing's energy consumption 1.1 The slowing of the growth in total energy consumption In 2008,Beijing's total energy consumption reached 63.437 million tons of standard coal,an increase of 586.6 thousand tons compared with the previous year.The increasing range was 1%,dropping 5.45%compared with the
文摘In this paper,using concentration data of PM2. 5in 2013 in China and referring to a lot of literature,we preliminary studied the pollution of fine particulate matter and summarized PM2. 5source apportionment in the key cities in China. Our results showed that PM2. 5showed significant spatial and temporal distribution; high surface concentrations of PM2. 5concentrated mainly in the North China Plain,the Sichuan Basin,Yangtze River Delta and other regions; the average annual concentration of PM2. 5was about 80μg / m3 in North China Plain; Seasonal changes in the concentration of PM2. 5was winter > spring > autumn > summer; fired sources,industrial sources,vehicle exhaust were the major sources of PM2. 5; motor vehicle exhaust mostly contributed 10%- 30% to PM2. 5. This review provides a fundamental understanding of PM2. 5source apportionment and serves as an important reference for future source apportionment studies to be widely conducted in China.
文摘Many environmental variables are frequently used to predict values of soil in locations where they are not measured. Digital soil mapping (DSM) has a long-standing convention to describe soils as a function of climate, organisms, topography, parent material, time and space. It is obvious that terrain, climate, parent material and organisms are used frequently in the prediction of soil properties while time and space factors are rarely used. Time is the indirect factor for the formation and development of soil. Moreover, it is very useful to explicit and implicit estimates of soil age for DSM. However, it is often difficult to obtain time factor. In the absence of explicit soil age data, geomorphologic data are commonly related to soil relative age. Consequently, this study adopts the geomorphologic types (genesis type of geomorphology) as surrogate to the time factor and analyzes its effect on DSM. To examine this idea, we selected the Ili region of northwestern China as the study area. This paper uses geomorphologic data from a new digital geomorphology map as the implicit soil age in predictive soil mapping. For this study, Soil-landscape inference model (SoLIM) was used to predict soil properties based on the individual representation of each sample. This model applies the terrain (topography), climate, parent material (geology) and time (geomorphologic type) to predict soil values in the study area where they are not measured. And the independent sample validation method was used to estimate the precision of results. The validation result shows that the use of geomorphologic data as surrogate to the time factor in the individual representation leads to a considerable and significant increase in the accuracy of results. In other words, implicit estimates of soil age by genesis type of geomorphology are very useful for DSM. This increase was due to the high purity of the geomorphologic data. This means that the geomorphologic variable, if used, can improve the quality of DSM. Predicted value through the proposed approach comes closer to the real value.
文摘In this paper,narrow-pulse power discharge is used to study the synergistic control of mercury and dioxins,in which 1,2,4-trichlorobenzene(TCB)was used as a dioxin analog,by using a selfdesigned experimental system.The competitive effects of NO,SO2 and HC1 on the TCB removal by non-thermal plasma are discussed.The influence of acid gas on TCB degradation is reflected in the competitive effect.NO has the greatest influence on TCB degradation efficiency.The oxidation efficiency of Hg°decreased by about 10%in all three acidic gas atmospheres,and the effect of each gas component on Hg()oxidation is complex.In the flue gas atmosphere of'acid gas+Hg°+TCB',the mechanism of the synergistic control of Hg°and TCB by the nonthermal plasma is different,which has competition and promotion relationship between each other.The contribution of various flue gas components to the results was complicated,but the overall experimental results show that the synergistic control effect of the system can continue to improve.According to the generated product backstepping,-OH plays an important role in the synergistic control of the degradation of Hg°and TCB.Through this study,we hope to provide basic research data for the collaborative control of flue gas in the incineration industry.
基金financially supported by the National Natural Science Foundation of China (No. 51602018)Beijing Natural Science Foundation (No. 2154052)+2 种基金China Postdoctoral Science Foundation Funded Project (No. 2014M560044)the Fundamental Research Funds for the Central Universities (FRF-GF-17-B7)National Key Technologies Research and Development Program of China:Key International Science and Technology Cooperation Projects (2016YFE0111500)
文摘A cryogenic scanning electron microscopy(cryo-SEM) technique was used to explore the shear-thickening behavior of Fe-ZSM5 zeolite pastes and to discover its underlying mechanism. Bare Fe-ZSM5 zeolite samples were found to contain agglomerations, which may break the flow of the pastes and cause shear-thickening behaviors. However, the shear-thickening behaviors can be eliminated by the addition of halloysite and various boehmites because of improved particle packing. Furthermore, compared with pure Fe-ZSM5 zeolite samples and its composite samples with halloysite, the samples with boehmite(Pural SB or Disperal) additions exhibited network structures in their cryo-SEM images; these structures could facilitate the storage and release of flow water, smooth paste flow, and avoid shear-thickening. By contrast, another boehmite(Versal 250) formed agglomerations rather than network structures after being added to the Fe-ZSM5 zeolite paste and resulted in shear-thickening behavior. Consequently, the results suggest that these network structures play key roles in eliminating the shear-thickening behavior.
文摘Effects of conservation methods of water samples on determination of total phosphorus were analyzed from aspects of methods of adding conserving agent, SS concentration, natural sedimentation time, conservation temperature and time. The results showed that SS concentration in water and natural sedimentation time had the greatest impact on the determination of total phosphorus, while the influence of methods of adding conserving agent, conservation temperature and time was relatively smaller. TP concentration in water samples conserved irregularly was higher than the standard value due to the existence of SS and microorganisms in water, and the deviation became larger with the increase of SS concentration in water. In addition, quality control measures and matters needing attention during the conservation process of water samples were put forward to improve the accuracy of TP concentration.
基金Supported by the National Natural Science Foundation of China(41171384,41271414and 41301529)
文摘[Objective] This study aimed to examine indicative roles of texture representing soil organic carbon presence and variability subsequent to cultivation under cold temperate climates with seasonal freeze-thaw events. [Method] Three chronosequences were selected for paired comparisons. Soil samples were collected at six depths with a 10 cm increment. Analysis of variance with general linear model and regression was performed for statistical analysis. [Result] In seasonally frozen soils where fragmentation of macroaggregates was stimulated, soil organic carbon level was positively associated with clay + silt proportion due to a wider textural range, better than sole clay content. Exponential function better fitted the experimental data to present progressively increased effectiveness of clay + silt content in maintaining carbon. Clay content explained 12%-41% and 14%-43% of variation via linear and exponential functions, respectively. Accordingly, clay + silt content explained 47%-65% and 46%-70%. [Conclusion] Texture reflected soil organic carbon occurrence as consequences of reclamation. For seasonally frozen soils with wider textural ranges, it is robust to adapt clay + silt content as dependent variable and exponential function. The generated algorithms provided an available pathway to estimate soil organic carbon losses following cultivation and to evaluate soil fertility.